Daily-level associations between PTSD and cannabis use among young sexual minority women.

INTRODUCTION: Sexual minority women have elevated trauma exposure and prevalence of posttraumatic stress disorder (PTSD) compared to heterosexual women and they are also more likely to use cannabis, although no research has examined relationships between PTSD and cannabis use in this population. Daily-level methodologies are necessary to examine proximal associations between PTSD and use.

METHODS: This study included 90 trauma-exposed young adult women who identified as sexual minorities (34.4% identified as lesbian and 48.9% identified as bisexual) and evaluated daily-level associations between their PTSD symptoms and cannabis use. Participants were assessed at two measurement waves, one year apart, each consisting of 14 consecutive daily assessments.

RESULTS: Cannabis use occurred on 22.8% of the days. Results from generalized linear mixed effects models showed that a person's mean level of PTSD symptom severity across days was strongly associated with same-day likelihood of cannabis use (OR=2.67 for 1 SD increase in PTSD score; p<0.001). However, daily deviation from one's average PTSD score was not associated with cannabis use on the same day.

CONCLUSIONS: Findings suggest that PTSD severity may confer general risk for cannabis use, rather than being a state-dependent risk factor.